Data survey shows no evidence to support claim

April 17, 1992

By Lynn Yarris, LCYarris@lbl.gov

Statistics do not support claims that low frequency
electromagnetic fields from power lines, electrical appliances,
etc., cause leukemia or any other form of cancer, says the
Physics Division's Dave Jackson, who is also a UC Berkeley
physics professor.

In a paper appearing in the April 15 issue of the "Proceedings
of the National Academy of Sciences", Jackson examines
historical data on the generation and consumption of electrical
power since 1900, and compares it to corresponding data on cancer
death and incidence rates.

"The conclusions from the data are that there cannot be any
significant cause of cancer from the use of electricity in
society," Jackson says. "There is no evidence to support the
claim that stray low frequency (50 or 60 hertz) electromagnetic
fields cause leukemia."

The data examined by Jackson showed that while the amount of
electrical power generated and consumed in this country since the
turn of the century has increased enormously, the age-adjusted
cancer death rate for the population as a whole shows only a
slight rise. Furthermore, when respiratory cancers, caused mainly
by the use of tobacco, are subtracted, the remaining death rate
from cancers has actually declined since 1940 -- a period when
per capita residential use of electric power increased
twentyfold.

The issue has been raised in recent years as to whether stray low
frequency electromagnetic fields from overhead electrical power
lines, transformers, or even household wiring and appliances are
hazardous to human health. Claims have been made that such
radiation can cause cancer, especially leukemia. Research on the
subject has been inconclusive.

"I wanted to look at the problem in a pragmatic way," Jackson
says, "in order to establish whether there is likely to be any
appreciable threat to most people from the stray fields
inevitably present in our increasing reliance on electrical
devices for work and play."

Jackson worked from statistics collected from a variety of
sources, including the U.S. Department of Energy, the Bureau of
the Census, the National Center for Health Statistics, and the
Office of Technology Assessment. As a measure of potentially
threatening electromagnetic fields, he looked not only at the per
capita residential power consumption, but also at the total
electric power generation per capita in this country, which
increased by 350 times, from 32,000 watt hours per year in 1902,
to 11.2 million watt hours per year in 1990.

"Power generation includes the losses in transmission," says
Jackson, "a component of the electricity distribution system
brought into question by those who suspect some cause and
effect."

Jackson notes that the early data on cancer are on cancer death
rates and not incidence rates of newly diagnosed cancers.
Reliable national data on trends in cancer incidence have only
been available since the late 1960s. However, even these data
show only a small (0.9 percent per year) increase in total
incidence rate, and, if anything, a decrease in the incidence of
leukemia. Furthermore, most of this increase is attributable to
forms of cancer for which there are known causes other than
electromagnetic fields.

Jackson says his conclusions will not come as a surprise to
scientists who have been studying the issue. The broad consensus
has been that the hazards posed by low frequency electromagnetic
fields are insignificant and that any possible risk is confined
to very small segments of the population which might possibly be
particularly susceptible for one reason or another.

"The average person has nothing to fear about sleeping next to an
electric radio or alarm clock, using a household appliance, or
walking under a high-tension power line," Jackson says.